include/litmus/gpu_affinity.h


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#ifndef LITMUS_GPU_AFFINITY_H
#define LITMUS_GPU_AFFINITY_H

#include <litmus/rt_param.h>
#include <litmus/sched_plugin.h>
#include <litmus/litmus.h>

void update_gpu_estimate(struct task_struct* t, lt_t observed);
gpu_migration_dist_t gpu_migration_distance(int a, int b);

static inline void reset_gpu_tracker(struct task_struct* t)
{
	t->rt_param.accum_gpu_time = 0;
}

static inline void start_gpu_tracker(struct task_struct* t)
{
	t->rt_param.gpu_time_stamp = litmus_clock();
}

static inline void stop_gpu_tracker(struct task_struct* t)
{
	lt_t now = litmus_clock();
	t->rt_param.accum_gpu_time += (now - t->rt_param.gpu_time_stamp);
}

static inline lt_t get_gpu_time(struct task_struct* t)
{
	return t->rt_param.accum_gpu_time;
}

static inline lt_t get_gpu_estimate(struct task_struct* t, gpu_migration_dist_t dist)
{
	int i;
	fpbuf_t temp = _fp_to_integer(t->rt_param.gpu_migration_est[dist].est);
	lt_t val = (temp >= 0) ? temp : 0;  // never allow negative estimates...

	WARN_ON(temp < 0);

	// lower-bound a distant migration to be at least equal to the level
	// below it.
	for(i = dist-1; (val == 0) && (i >= MIG_LOCAL); --i) {
		val = _fp_to_integer(t->rt_param.gpu_migration_est[i].est);
	}

	// minimum value is 1 (val is 0 if we haven't run with local affinity yet)
	// TODO: pick a better default min-value.  1 is too small.  perhaps
	// task execution time?
	return ((val > 0) ? val : 1);
}

#endif